SLUUDM5 March 2026 MSPM0G1507 , MSPM0G1519 , MSPM0G3507 , MSPM0G3519
The FOC algorithm uses the reverse drive function to change the direction of the motor rotation when pUserInputRegs->isdCfg.b.rvsDrEn and isdEn are both set to 1b and the ISD determines the motor spin direction to be opposite to that of the commanded direction. This function is only valid in Sensorless FOC.
Reverse drive includes synchronizing with the motor speed in the reverse direction, reverse decelerating the motor through zero speed, changing direction, and accelerating in open loop in forward (or commanded) direction until the device transitions into closed loop in forward direction.
FOC algorithm provides the option of using the forward direction parameters or a separate set of reverse drive parameters by configuring pUserInputRegs->rvsDrvCfg.b.revDrvConfig.
Follow these recommendations if the motor fails to resynchronize in reverse direction:
The following figure shows the motor speed curve under the reverse drive transition.